Cosmetic composition comprising monosaccharides or polysaccharides, uses and treatment methods

ABSTRACT

A cosmetic and/or dermatological composition includes comprising, as an active ingredient, at least one mono or polysaccharide, constitutive of a pectic substance coming from a plant of the Lemnaceae family. The invention includes also its use, inter alias, for the care of the skin and/or its appendages, its use in order to treat manifestations of cutaneous ageing as well as the manifestations of inflammation and cutaneous irritation. The invention relates also to the cosmetic process of treatment of the skin using the aforementioned composition.

The present invention relates to the cosmetic and dermatological fields,and has as an aim a cosmetic and/or dermatological compositioncomprising, as an active ingredient, at least one mono orpolysaccharide, constitutive of a pectic substance coming from a plantof the Lemnaceae family.

The plants of the Lemnaceae family are monocotyledon angiosperm plants.The Lemnaceae family belongs to the order of Arales and regroups fourgenus: Lemna, Spirodela, Wolffia and Wolffiela, representing about up tothirty species in the world. Five of them belong to the European flora:Lemna triscula, Lemna minor, Lemna gibba, Spirodella polyrrhiza, Wolffiaarrhiza.

The plants of the Lemnaceae family are commonly called “duckweeds” orminor duckweed. They are small aquatic perennial plants, floating onsurface of water or sometimes between two waters, without stems norleaves, reduced to a simple horizontal lenticular corpuscle and rounded,called frond. They have one or more filiform roots, not ramified andwithout absorbing hair, playing a role of anchoring.

Duckweeds have various uses, they are sometimes produced for food use;collected and dried, they are sold in certain dietetic stores. Incertain developing countries, duckweeds are used in animal food, such aspoultry or fish food. Their success is due to the very high proteincontent; indeed, proteins account for 35 to 50% of dry weight, that isto say as much as the protein quantity present in Soya beans. Moreover,duckweeds have other determining advantages: by their very fast growth,they contribute to cleanse stagnant waters; they are thus usedeffectively as regards decontamination.

The plants of the Lemnaceae family (as all plants) present thecharacteristic to contain particular polysaccharides composing thestructure of the vegetable cell walls: pectins. The pectins of duckweedsare particular, notably, in their composition. These are calledapiogalactoronan or lemnan, with regard to the pectins of the plantsspecies Lemna minor.

The pectic substances, or pectins, are macromolecule of a glucidicnature, essentially composed of galacturonic acids.

The monomeric motif for the pectic substances is the α D-galaturonicacid, the skeleton of the pectic substances is thus formed by dependentgalacturonic acids α [1-4] linked, this chain constituting thepolygalacturonic acid or pectic acid. In general, pectic substances havea more complex structure resulting from the substitution of certaingroups on the principal chain.

Duckweeds have a particular pectic substance: the apiogalactoronan. Thepectic substance of the duckweed Lemna minor is ramified. Thisapiogalactoronan was isolated from the duckweed and was characterizedfor the first time by Hart and Kindel in 1970.

The composition of the apiogalactoronan is particular. Indeed, thesaccharidic chain of the pectic substance of Lemna minor (or lemnan) iscomposed of D-galacturonic acid (64%) and of D-apiose (25%) as principalcomponents, as well as galactose, arabinose, rhamnose and xylose.

Apiose is not a very common sugar, it is a pentose with ramified chains.It was first described by Bell et al. (1954) as a component ofpolysaccharides of Posidonia australis.

It is known to use pectic substances in many fields, particularly incertain therapeutic fields where they are used as a thickening agent oras excipient.

However a use of saccharides, constituents of a pectic substance comingfrom a plant of the Lemnaceae family, as an active ingredient, in thecosmetic and/or pharmaceutical field is not known yet.

However, the inventors of the present invention have unexpectedly andsurprisingly noted that the mono- or polysaccharides constituents of apectic substance, coming from a plant of the Lemnaceae family, presentspecific biological activities, which make them directly usable incosmetic, dermatological and pharmaceutical preparations or compositionsto external topic use.

Thus, the main object of this invention consists of a cosmetic and/ordermatological composition comprising, as an active ingredient, at leasta mono- or polysaccharide, constituent of a pectic substance coming froma plant of Lemnaceae family.

The inventors noted in particular that these saccharides presentanti-inflammatory, calming, hydrating, protective and significantanti-aging actions within the framework of the above mentioned use.Moreover, these saccharides present an anti-hyaluronidase effect, thatis to say that they inhibit the activity of the hyaluronidases, enzymeswhich hydrolyze the hyaluronic acid.

Preferentially, the composition according to the invention willcomprise, as an active ingredient, the pectin contained in the plants ofthe Lemnaceae family.

According to a particular way of realization of the invention, thepolysaccharide coming from Lemnaceae family is a pectic substancecomprising at least an apiose motif.

According to another way of realization of the invention, thecomposition according to the invention will comprise, as an activeingredient, a monosaccharide, the apiose, constituent of a pecticsubstance coming from Lemnaceae family.

Moreover, according to another way of realization of the invention, theplants of the Lemnaceae family are plants of the Lemna genus. Of course,the pectic substances can be obtained from at least any of the manyvarieties and species belonging to the Lemna genus.

Preferentially, the pectic substances are obtained from at least a plantof the Lemna minor species.

According to the invention, the term “active ingredient” can be definedas being all the molecules or all unit of molecules likely to bringmodifications or modulations to the operation of a biological system.

Active compounds according to the invention, that is the mono- orpolysaccharides constituents of the pectic substance, are obtained frompectin. The mono- or polysaccharides constituents of a pectic substancemean all pectic substances as well as all saccharides or saccharidicchains which compose them. The mono- or polysaccharides constituents ofa pectic substance thus indicate the pectins which were more or lesshydrolyzed.

An essential characteristic of the invention is that these pecticsubstances, from which are drawn the mono- or polysaccharides, come froma plant of the Lemnaceae family.

Thus, any method of extraction and/or purification known by the personskilled in the art can be used to prepare the glucidic compoundsaccording to the invention.

Of course, the effective amount of active ingredient, constituting thecomposition, corresponds to the necessary amount in order to obtain thedesired result.

According to an advantageous way of realization of the invention, themono- or polysaccharide, constituent of a pectic substance coming from aplant of the Lemnaceae family, is present in a quantity representingfrom 10⁻⁵% to 20% of the total weight of the composition and,preferentially, in a quantity representing from 10⁻⁴% to 5% of the totalweight of the composition.

According to an advantageous way of realization of the invention, theactive compounds above mentioned are beforehand solubilized or dispersedin one or more cosmetically or pharmaceutically acceptable solvents suchas water, ethanol, propanol or isopropanol, propylene glycol, butyleneglycol, dipropylene glycol, diglycols ethoxylated or propoxylated,cyclic polyols, petroleum jelly, a vegetable oil or any combinations ofthese solvents.

According to another advantageous way of realization of the invention,the above mentioned active compounds are beforehand solubilized in acosmetic or pharmaceutical vector such as liposomes or are adsorbed onpowdery organic polymers, mineral supports such as talc and bentonites,and more generally solubilized in, or fixed on, any cosmetically orpharmaceutically acceptable vector.

The composition, according to the present invention, can be a cosmeticor dermatological or pharmaceutical composition. According to thisinvention, the composition is preferably cosmetic in nature, since it isaimed at improving the cutaneous appearance and general cutaneousperformance of the individual who uses it.

According to the present invention, the composition is preferably acosmetic and/or dermatological composition adapted for topical cutaneousapplication through an acceptable cosmetic or dermatological medium.

It is evident that the invention relates to mammals in general, and morespecifically, to humans. Whatever forms the invention takes, thecomposition, according to the invention, can be ingested, injected, or,applied to skin (to all cutaneous zones of the body), hair, nails ormucous membranes. According to the mode of administration, thecomposition related to the invention can be presented under all galenicforms normally used.

The compositions related to the invention are preferably presented undera galenic form adapted for cutaneous topical administration. They coverall the cosmetic and dermatological forms. These compositions mustcontain an acceptable cosmetic or dermatological medium. That is to say,a medium that is compatible with skin and hair.

These compositions can take the form of an aqueous, hydro-alcoholic oroil solution; or the form of an oil-in-water, water-in-oil emulsions orin multiple emulsions. They can also be used as creams, as suspension oras a powder, adapted for application to skin, mucous membranes, lipsand/or hair.

These compositions can also be more or less fluid or solid and can takethe form of creams, lotions, milks, serums, ointments, shampoo, gel,paste and mousse. It can also take a solid form like a stick, or it canbe used, on the skin, in aerosols. It can also be used as a skin careproduct and/or as make-up for skin.

Concerning injection, the composition related to the invention can beaqueous or oil based lotions or a serum. For application to the eyes,the composition can be used as drops whereas for ingestion it can beused as capsules, granules, syrup or pills.

Moreover, these compositions can include all of the additives that areusually considered for use in this application as all the possibleadditives necessary for their formulation such as solvents, thickeners,diluents, anti-oxidants, colorants, solar filters, auto-tanningproducts, pigments, fillers, preservatives, perfumes, odor absorbers,pharmaceutical and cosmetic active ingredients, essential oils,vitamins, essential fatty acids, tensioactivators, filmogen polymersetc.

In all the cases, the person skilled in the art will attempt tocarefully consider the selection of adjuvants, as well as theirproportions, not to compromise the advantageous properties of thecomposition relating to the invention. These adjuvants can, for example,correspond to 0.01% to 20% of the total weight of the composition.

When the composition according to the invention is an emulsion, thefatty phase can represent 5% to 80% by weight, but preferably it wouldrepresent 5% to 50% of the weight with respect to the total weight ofthe composition. Emulsifiers or co-emulsifiers used in the compositionare selected among those that are classically used in the domain underconsideration. For example, they can be used in a proportion of 0.3% to30% by weight relative to the total weight of the composition.

Of course, the person skilled in the art should select the complementarycompounds for the composition, active or non-active, as well as theamounts of the complementary compounds in such a way that theadvantageous properties of the composition will not be perceptiblyaltered by the envisaged addition.

The compositions, according to the present invention, can be appliedmost notably as a cosmetic or pharmaceutical composition for use on theskin, mucous membranes and/or semi-mucous membranes.

The compositions can be applied, particularly, as a skin protectionand/or skin care products, or as an anti-wrinkle and/or anti-agingcomposition.

We can also consider an application in the field of facial and bodymake-up compositions, such as lipsticks, foundation, tinted creams, darkcircle sticks, or sunscreen and artificial tanning compositions.

The compositions of the invention can be used in a great number oftreatments, notably cosmetic and dermatological treatments. They cantake the form of cosmetic compositions used for skin, lips and/or hairtreatment, protection, care and make-up removal and/or cleaning, as wellas for make-up applications to skin, lips, eye lashes and/or the body.

The composition relating to the invention can also consist of solidpreparations such as soap and other cleaning bar soaps.

The composition can also be made in aerosol form in which it can bemixed with pressurized propulsion agents.

The composition can also be used orally, for example, as toothpaste. Thecomposition of the invention can be applied as a cosmetic,dermatological or pharmaceutical composition to be used orally. Thesecan take the form of drinkable solution, syrups, tablets, sugar coatedpills, capsules, or even as food and nutritional supplements.

According to the invention, we can add to the composition of theinvention, other active agents intended for the prevention and/ortreatment of the manifestations of cutaneous aging, and/or skinprotection from external aggressions.

The invention has, as well, for object the use, as an active ingredient,of at least a mono- or polysaccharide, constituent of a pectic substancecoming from a plant of the Lemnaceae family, such as previously defined,in or for the preparation of a composition; the compounds or thecomposition comprising it are used in order to fight in a curativeand/or preventive way, against the signs of cutaneous aging, but also inorder to improve the aspect of the skin and its appendages. In a moregeneral manner, the composition according to the invention will have anactivity in the care of the skin and its appendages.

The care of the skin and/or its skin appendages is the process ofconserving or re-establishing the healthy functioning of skin and/or itsskin appendages or the process of providing the means that serve topreserve or improve their appearance and/or texture.

Thus, skin care refers to hydration, appeasement, and protection againstall types of aggression, especially from the sun, as well as the fightto prevent the manifestations of aging, particularly cutaneousmanifestations of aging.

Manifestations of cutaneous aging include all the modificationsregarding external appearance of skin due to aging. Examples of thesemodifications include wrinkles and fine lines, limp skin, slackenedskin, slimmer looking skin, loss of elasticity and/or skin tone, dullskin, and skin which lacks radiance. It also includes internal skinmodifications that do not translate directly into changes in externalskin appearance. An example of these internal modifications is thedegradation that occurs internally in skin resulting from consecutiveexposure to UV radiation.

The phrase “to improve the appearance of the skin” refers to all thephenomena which are likely to have for consequences a visual improvementof the state of the skin. The skin will have a better appearance; itwill be, for example, much more beautiful, firm and/or smooth. All thesmall imperfections will be decreased or removed. The papyraceous aspectof the skin, for example, will be attenuated.

In addition, according to an essential characteristic, the inventionrelates to the use of at least a mono- or polysaccharide, constituent ofa pectic substance coming from a plant of the Lemnaceae family, in orderto maintain and/or to stimulate the cutaneous hydration and/or in orderto fight against the drying effect on the skin.

Indeed, the mono- or polysaccharides, constituents of a pectic substancecoming from a plant of the Lemnaceae family, have an anti-hyaluronidaseaction. That is they inhibit the activity of the enzymes, thehyaluronidases, which degrade the hyaluronic acid. However, thehyaluronic acid is the main glycosaminoglycan of the dermis and itexerts a very important role. It is indeed known that skin aging, aswell as the drying effect observed in particular in old skins is, for avery significant part, related to a loss of hyaluronic acid.

It was observed that the mono- or polysaccharides, constituents of apectic substance coming from a plant of the Lemnaceae family, accordingto the invention, has many actions in the skin; in particular, it ispossible to fight against the cutaneous aging phenomena and enables theskin to be protected against all types of external aggressions. Thus,the composition according to the invention can be used to protectkeratinous substrates and, particularly, the skin and its appendagesfrom all types of external aggression.

The use of these compounds, or the composition including it, will allowthe keratinous substrates to be protected and to better resist stressproduced on them by the environment. The phrase “external aggressions”refers to the aggressions which the environment can produce. Theseaggressions can be of chemical, physical, biological or thermal origin.As an example, we can quote aggressions such as pollution, UV,frictions, water with strong limestone concentration, variations intemperature or potentially irritating products such as tensioactives,preservatives or fragrances.

The mono- or polysaccharides, constituents of a pectic substance comingfrom a plant of the Lemnaceae family, have an effective action on thelevel of the cutaneous barrier. So, these compounds reinforce thebarrier function of the skin. They promote, thus, tissue regeneration.So the compounds or the composition according to the invention can beused to accelerate tissue regeneration and/or skin wound healing.

In addition, the invention also relates to the use as an activeingredient, of the mono- or polysaccharides, constituents of a pecticsubstance coming from a plant of the Lemnaceae family, in or for thepreparation of a composition, the compounds or the composition beingintended to treat the appearance of inflammation and cutaneousirritation. The composition, indeed, is very well adapted to sensitiveand delicate skins.

The compounds or the composition have a particularly effective action onthe fight against allergic phenomena, and in particular on theirconsequences to the skin. Thus, another aspect of the invention, is theuse of the compounds mentioned above, or the composition containingthem, in order to fight allergic phenomena and/or the appearance ofcutaneous inflammation.

In addition, the compounds or the composition, according to theinvention, have a particularly effective action on the fight against themicrobial agents. The compounds or the composition containing it, thushave antimicrobial properties, that is anti-bacterial, anti-fungic,virucides or anti-protozoa properties. The composition will thus have aparticularly useful application in the treatment of cutaneousinfections, of inflammatory phenomena of the skin and/or the hair, alsoin all hair and/or skin diseases having a microbial origin. Moreparticularly, the composition according to the invention will haveeffectiveness in the treatment of the skin and in the fight against thebacteria. The compounds or the composition according to the inventionwill thus have a bacteriostatic effect.

Thus, the compounds or the composition containing it, according to theinvention, can be used in the treatment of the local troubles on theskin. Moreover, they will make it possible to fight, in a particularlyeffective manner, acne phenomena and/or all sorts of infections orinflammatory reactions.

Another characteristic of the composition according to the invention, isits effective action in cell detoxification, i.e. the compounds orcomposition containing it will be useful to detoxify cells, andparticularly, skin's cells.

These various properties can be used to carry out compositions intendedto protect skin against external aggressions caused, in particular, bysolar radiation or by other physical, chemical or biological agents; orto carry out compositions able to fight skin aging, and to care of it.

According to another aspect, the present invention relates to a cosmeticprocess of treatment of the skin, particularly old skins, and/or tofight cellular aging phenomena consisting in applying to the surface ofthe skin an effective amount of the composition such as previouslydefined, i.e. containing at least a mono- or polysaccharide, constituentof a pectic substance coming from a plant of the Lemnaceae family, toobtain the desired effect.

The present invention relates, in the same way, to a cosmetic process oftreatment in order to protect the skin and its appendages against alltypes of external aggression, and/or to reinforce the barrier functionof the skin and its appendages.

Another aspect related to the present invention concerns a cosmeticprocess for the treatment of skin in order to favor skin wound healingand tissue regeneration, but also in order to favor cellulardifferentiation.

The present invention also relates to a cosmetic process of treatment inorder to treat allergic and/or inflammation phenomena of the skin; alsoin order to fight against microbial agents, consisting in applying tothe surface of the skin and/or its appendages, an effective amount ofthe composition such as previously defined.

Particular modes of realization of this cosmetic process of treatmentalso result from the preceding description.

The process of cosmetic treatment related to the invention can beimplemented, particularly, when applying the cosmetic compositions hereabove according to methods habitually used for compositions, such as theapplication of creams, gels, serums, lotions, milks, shampoo, and suncreams, on skin, hair and as a toothpaste applied to the gums.

Other advantages and characteristics of the invention will becomeapparent by reading the following examples, by way of an illustrativeand unrestrictive demonstration of data.

EXAMPLE 1 Preparation of an Extract Containing Mono- or Polysaccharides,Constituents of a Pectic Substance, Coming From a Plant of the FamilyLemnaceae

Duckweeds, of the Lemna genus, are collected on the surface of water,then washed in very pure water. 5 kg of these freshly collected, orpreserved by freezing, are crushed very finely and homogenized, using anultra-turrax blender, in 2 to 5 volumes of a saline solution, preferablyin a sodium chloride solution. This operation is carried out at atemperature between 4 and 90° C., preferably at a temperatureapproximately equal to 40° C.

Then the crushed extract undergoes a stage of filtration and/orcentrifugation; the filtrate is eliminated. This extraction operation insaline solution, followed by a stage of centrifugation, is carried outthree times, each time the filtrates are isolated. The residue isrecuperated and is treated in the same manner, by extraction underagitation then by centrifugation and/or filtration, three times, inwater. Then a crushed extract is obtained containing the cell walls ofthe duckweeds. According to an alternative of the process of extraction,this stage can be carried out in the presence of enzymes, preferably ofprotease and/or cellulase type.

The pectin extraction, present in the cell walls of the duckweeds, isperformed in aqueous solution containing a chelating agent, the ammoniumoxalate, with a concentration between 0.02 and 0.1 M (EDTA or sodiumpolyphosphate can also be used). This extraction is realized in acidicconditions, with a pH between 2 and 5 (reached with the use ofhydrochloric acid), at a temperature between 4 and 90° C.

Pectins thus extracted are precipitated by salts or alcohol. They arethen collected and dialyzed to be purified. Pectins obtained can be putin aqueous solution, constituting a first usable form of the extractaccording to the invention.

Pectins obtained can be used in this native form or in a more or lesshydrolyzed form, that is a more or less depolymerized form. In thiscase, pectin hydrolysis can be carried out by various pectoliticenzymes; this hydrolysis can also be carried out in a chemical way,preferably in acid medium.

The hydrolysis involves the formation of residues of, more or less, lowmolecular weights; thus we obtain polysaccharide, constituents of apectic substance, of various sizes.

A total hydrolysis will release all the pectic components, and willallow a mix, mainly made up, of monosaccharides, mainly containinggalacturonic acid and apiose.

The various depolymerized pectin compounds, more or less purified,constitute forms of extract usable to prepare the composition accordingto the invention.

According to a particular mode of realization of the invention, pectinwill be completely hydrolyzed so as to obtain monosaccharideconstituents of a pectic substance. This hydrolysis, followed by a stageof purification, will allow a solution containing, almost exclusively,apiose.

This solution will constitute a form of extract directly usable to carryout a cosmetic composition containing apiose.

EXAMPLE 2 Preparation of Compositions

These compositions were obtained by simple combination of the variouscomponents. The quantities indicated are expressed by percentage weight.1 - Emulsion oil in water Oily phase: Montanov 68 (Cetearyl Alcohol andCetearyl Glucoside) 5.00% Oil of Jojoba 5.00% Oil Petroleum jelly 5.00%Isopropyl Palmitate 7.00% Aqueous phase: Glycerin 5.00% Allantoïne 0.10%extract of example 1 5.00% Sepigel 305 (Polyacrylamide, C13-14Isoparaffin and 0.30% Laureth-7) Conservative 0.50% Perfume 0.50% Waterqsp 100% 2 - Freezing Carbopol Ultrez 10 (ground with 2%) 25%Triethanolamine 0.50% Extract of example 1 5.00% Conservative 0.20% EDTA(sequestering) 0.10% Perfume 0.50% Water qsp 100% 3 - Lotion MonoPropylene Glycol 1.00% Allantoïne 0.30% Glycerin 1.00% Cetiol HE (Peg-7Glyceryl Cocoate) 1.00% Extract of example 1 5.00% Conservative 0.20%Perfume 0.50% Water qsp 100%

1. Cosmetic and/or dermatological composition comprising, as an activeingredient, in an physiologically acceptable medium, an effective amountof at least a mono- or polysaccharide, constituent of a pectic substancecoming from a plant of the Lemnaceae family.
 2. Composition according toclaim 1 characterized in that the polysaccharide, coming from a plant ofthe Lemnaceae family, is a pectic substance.
 3. Composition according toclaim 1 characterized in that the polysaccharide coming from theLemnaceae family is a pectic substance comprising at least an apiosemotif.
 4. Composition according to claim 1 characterized in that themonosaccharide, constituent of a pectic substance coming from a plant ofthe Lemnaceae family, is the apiose.
 5. Composition according to claim 1characterized in that the plants of the Lemnaceae family are of Lemnagenus.
 6. Composition according to claim 5 characterized in that theplants belong to the Lemna minor species.
 7. Composition according toclaim 1 characterized in that the mono- or polysaccharide, constituentof a pectic substance coming from a plant of the Lemnaceae family, ispresent in a quantity representing from 10⁻⁵% to 20% of the total weightof the composition and, preferentially, in a quantity representing from10⁻⁴% to 5% of the total weight of the composition.
 8. Compositionaccording to claim 1 characterized in that it takes a cosmetic and/ordermatological form adapted to topical cutaneous administration for theskin, mucous membranes and/or the skin's appendages, comprising apharmaceutically or cosmetically acceptable medium.
 9. Compositionaccording to claim 1 characterized in that the active compounds arebeforehand solubilized or dispersed in one or more cosmetically orpharmaceutically acceptable solvents such as water, ethanol, propanol orisopropanol, propylene glycol, butylene glycol, dipropylene glycol,diglycols ethoxylated or propoxylated, cyclic polyols, petroleum jelly,a vegetable oil or any combinations of these solvents.
 10. Compositionaccording to claim 1 characterized in that the active compounds arebeforehand solubilized in a cosmetic or pharmaceutical vector, such asliposomes, or are adsorbed on powdery organic polymers, mineral supportssuch as talc and bentonites, and more generally solubilized in, or fixedon, any cosmetically or pharmaceutically acceptable vector. 11.Composition according to claim 1 characterized in that it takes the formof an aqueous, hydro-alcoholic or oil solution; or the form of anoil-in-water, water-in-oil emulsions or in multiple emulsions; or theform of creams, suspension or powder; these compositions can be more orless fluid or solid, and take the form of a cream, a lotion, a milk, aserum, an ointment, a shampoo, a gel, a paste, a mousse or a stick. 12.Use of at least a mono- or polysaccharide, constituent of a pecticsubstance coming from a plant of the Lemnaceae family, such as definedby claim 1, as an active ingredient, in or for the preparation of acomposition; the compounds or the composition are used in order totreat, in a curative and/or preventive way, the signs of cutaneousaging, and/or to improve the appearance of the skin and/or itsappendages.
 13. Use of at least a mono- or polysaccharide, constituentof a pectic substance coming from a plant of the Lemnaceae family, suchas defined by claim 1, as an active ingredient, in or for thepreparation of a composition; the compounds or the composition are usedto favor tissue regeneration and/or skin wound healing.
 14. Use of atleast a mono- or polysaccharide, constituent of a pectic substancecoming from a plant of the Lemnaceae family, such as defined by claim 1,as an active ingredient, in or for the preparation of a composition; thecompounds or the composition being intended to fight against thecutaneous allergic phenomenon.
 15. Use of at least a mono- orpolysaccharide, constituent of a pectic substance coming from a plant ofthe Lemnaceae family, such as defined by claim 1, as an activeingredient, in or for the preparation of a composition; the compounds orthe composition being intended to fight against the appearance ofcutaneous inflammation.
 16. Use of at least a mono- or polysaccharide,constituent of a pectic substance coming from a plant of the Lemnaceaefamily, such as defined by claim 1, as an active ingredient, in or forthe preparation of a composition; the compounds or the composition beingintended to maintain and/or to stimulate the cutaneous hydration and/orin order to fight against the drying effect on skin.
 17. Use of at leasta mono- or polysaccharide, constituent of a pectic substance coming froma plant of the Lemnaceae family, such as defined by claim 1, as anactive ingredient, in or for the preparation of a composition; thecompounds or the composition being intended to detoxify the cells. 18.Use of at least a mono- or polysaccharide, constituent of a pecticsubstance coming from a plant of the Lemnaceae family, such as definedby claim 1, as an active ingredient, in or for the preparation of acomposition; the compounds or the composition being intended to fightagainst microbial agents and notably against bacteria.
 19. Use of atleast a mono- or polysaccharide, constituent of a pectic substancecoming from a plant of the Lemnaceae family, such as defined by claim 1,as an active ingredient, in or for the preparation of a composition; thecompounds or the composition being intended to protect the skin and/orits appendages against external aggressions, and/or to reinforce thebarrier function of the skin.
 20. Use of at least a mono- orpolysaccharide, constituent of a pectic substance coming from a plant ofthe Lemnaceae family, such as defined by claim 1, as an activeingredient, in or for the preparation of a composition; the compounds orthe composition being intended for their anti-hyaluronidase action. 21.Cosmetic process of treatment in order to treat aged skins and/or tofight cellular aging phenomena, and/or to protect the skin and itsappendages against external aggressions, and/or to reinforce the barrierfunction of the skin and its appendages, consisting in applying, to theskin's surface and/or to the appendages, an effective amount of thecomposition such as defined according to claim
 1. 22. Cosmetic processof treatment in order to favor wound healing and/or tissue regeneration,and/or to favor cellular differentiation, consisting in applying, to theskin's surface and/or to the appendages, an effective amount of thecomposition such as defined according to claim
 1. 23. Cosmetic processof treatment in order to treat allergic and/or inflammation phenomena,and/or in order to fight against microbial agents, consisting inapplying, to the skin's surface and/or to the appendages, an effectiveamount of the composition such as defined according to claim 1.